The present invention relates generally to the field of database performance, and more particularly to maintaining high-demand retrieval data in cache.
In data oriented environments, data access often exhibits patterns of behavior. For example, data access requests related to tickets to a certain concert that have just gone on sale, the latest new movie recording release, and sales of airline tickets as a holiday approaches; all point towards elements of certain database tables and data that will be more frequently accessed than other portions of data. Current relational database management systems (RDBMS), and specifically, pre-caching methodologies often don't recognize and adapt to these trends in the most efficient way.
Many RDBMSs include indexing technology that enables sub-linear data lookup to improve performance, as linear search is inefficient for large databases. In simplistic terms a database index is best compared to that of an index of a book, which allows one to determine a page to directly turn to, to find the topic or information of interest, rather than having to read sequentially through the book to find particular information.
RDBMS performance is tightly integrated to the location of where the data is stored. If the data is to be retrieved from physical disk it is significantly slower than direct retrieval from machine cache; in some cases from ten thousand to one million times slower. Within todays RDBMS engines there are some techniques to attempt to improve latency issues of retrieval from physical disk; however, they have limited effectiveness.